1. Division of Gastroenterology, University of Pennsylvania , Philadelphia, PA , USA
2. Department of Family Medicine, Warren Alpert Medical School, Brown University , Providence, RI , USA
3. Warren Alpert Medical School, Brown University , Providence, RI , USA
4. Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA , USA
5. Center for the Treatment and Study of Anxiety, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA , USA
6. Division of Gastroenterology, Warren Alpert Medical School, Brown University , Providence, RI , USA
7. Gastroenterology Associates, Inc , Providence, RI , United States